Questions and Answers - Aircraft Instrument | Aircraft Systems

Questions and Answers - Aircraft Instrument

Study Aid Questions

Fill in the Blanks

1. There are usually two parts to any instrument or instrument system. One part ______ the situation and another part to ______ it.

2. Original analogue flight instruments are operated by ______ pressure and the use of ______.

3. 3 fundamental pressure‐sensing mechanisms used in aircraft instrument are the ______, the ______ , and the ______ sensing device.

4. Modern high performance aircraft use a digital air data computer that converts ______ into ______.

5. ADCs receive input from the ______ sensing devices and process them for use by numerous ______.

6. Altimeters that measure an aircraft’s ______ by measuring ______ of the atmosphere are known as ______ altimeters.

7. Digital flight instruments perform all of the calculations for ______ in the ADC.

8. Many high performance aircraft are equipped with ______ for monitoring Mcrit.

9. A ______ is an electric system used for transmitting information from one point to another.

10. Autosyn systems are distinguished from Magnasyn systems by the fact that the transmitter and indicator rotors used are ______ magnets rather than ______ magnets.

11. The tachometer indicates the speed of the ______ of a reciprocating engine.

12. Some turbine engines use ______ for rpm indication, rather than ______ system.

13. An accelerometer is used to monitor ______ acting upon an airframe and are used in ______ navigation systems.

14. Modern aircraft AOA sensors units send output signals to the ______.

15. Solid state magnetometers can not only sense the ______ to the earth magnetic poles, but also the ______ of the flux field.

16. Gyro instruments are driven by: ______ , ______ or ______.

17. The attitude indicator, or ______ , provides ______ and ______ information.

18. Automatic pilot systems are capable of keeping aircraft stabilized ____________, and ______.

19. The four basic components of an autopilot system are:
       ________________     ________________
       ________________     ________________

20. The Electronic Attitude Director Indicator (EADI) is an advanced version of ______ and ______ indicators.

21. The ______ system automatically monitors the airframe and engine systems and alerts the flight crew in case of a system failure.

22. The highest level of automated flight system is the ______.

23. The FMS coordinates the adjustment of ____________, and ______ parameters either automatically or by instructing the pilot how to do so.

24. When an aircraft is to be operational under IFR, an altimeter test must have been performed within the previous ______ months.

25. Compass magnetic deviation is caused by ______ interference from ferrous materials and operating ______ components in the cockpit.


1. Direct sensing instruments sense and display the information all in one instrument. TRUE/FALSE

2. The three basic kinds of instruments are classified as: flight instruments, engine instruments, and environmental control instruments. TRUE/FALSE

3. In a Bourdon tube the higher the pressure of the fluid, the more the tube straightens. TRUE/FALSE

4. Many flight instruments use a Bourdon type of sensing device. TRUE/FALSE

5. Solid state pressure sensing systems are internal sensing systems. TRUE/FALSE

6. The engine pressure indicator (EPR) compares the total exhaust pressure to the pressure of the ram air at the inlet of the engine. TRUE/FALSE

7. True airspeed is the relationship between the ram air pressure and static air pressure. TRUE/FALSE

8. The calculations of calibrated airspeed for modern aircraft with digital instruments are performed by the ADC. TRUE/FALSE

9. Aircraft with direct current systems (DC) often use synchro systems for transmitting information from one point to another. TRUE/FALSE

10. Tachometers used for turbine engines monitor the speed of the compressor section of the engine. TRUE/FALSE

11. Two types of Angle of Attack sensors used in aircraft are the vane type which uses an alpha vane externally mounted to the outside of the fuselage and the other type uses two slots in a probe that extends out of the side of the fuselage. TRUE/FALSE

12. Some AOA systems incorporate a stick pusher actuator that pushes the control yoke backwards to lower the nose of the aircraft. TRUE/FALSE

13. Two common application of thermocouples are: cylinder head temperature in reciprocating engines and exhaust gas temperature in turbine engines. TRUE/FALSE

14. Total air temperature (TAT) is the static air temperature minus any lowering in temperature caused by flying at high altitudes. TRUE/FALSE

15. Magnetic deviation, variation and dip errors are errors associated with a magnetic compass? TRUE/FALSE

16. The process for knowing how to adjust for magnetic variation is known as swinging the compass. TRUE/FALSE

17. Ring Laser Gyros (RLG), Microelectromechanical systems and Attitude Heading and Reference Systems (AHRS) are examples of attitude and directional systems used on modern aircraft. TRUE/FALSE

18. The sensing elements of an autopilot system are: the attitude and directional gyros, the turn coordinator, magnetic compass, and an altitude control. TRUE/FALSE

19. The output elements of an autopilot system are the servos that cause actuation of the flight control surfaces. TRUE/FALSE

20. The electronic flight instrument system replaces the attitude indicator and vertical gyro by cathode ray tubes (CRT) or LCDs that display EADI and EHSI presentations. TRUE/FALSE

21. The EICAS monitors engine and airframe parameters and doesn’t utilize traditional gauges. TRUE/FALSE

22. Maintenance personnel can access the EICAS to access data related to a failure event. TRUE/FALSE

23. The master caution lights on the enunciator panel can not be cancelled by the flight crew. TRUE/FALSE

24. Instrument panels are usually shock mounted to absorb high frequency, high‐amplitude shocks. TRUE/FALSE

25. The original equipment manufacturer will put colored range markings on the instrument face in accordance with the type certificate data sheet. TRUE/FALSE

Knowledge Application Questions

1. What is used as a reference for range marking instruments?

2. What does a yellow arc on an instrument dial indicate?

3. What aircraft instrument may be used to check a manifold pressure indicator for correct indication?

4. What indication errors may be found in altimeters?

5. What flight instruments are usually connected to a pitot‐static system?

6. What is required after replacement of components connected to a pitot‐static system?

7. What methods are used to drive turn‐and‐bank indicators?

8. What is a synchro‐type remote indicating system?

9. What does a tachometer indicate?

10 What type of indicating system is used to measure the turbine‐engine exhaust gas temperature?

11 What is the meaning of swinging a compass?

12 Name the three types of basic instruments used in an aircraft flight station?

13 What does an engine pressure indicator (EPR) compare?

14. What equipment performs the calculation of calibrated airspeed for modern aircraft with digital instruments?

15 Describe the two types of Angle of Attack sensors used in aircraft.

16. What are the two most common applications of thermocouples?

17. What type of system does monitor engine and airframe parameters and does not utilize traditional gauges.

18. What system can be accessed by maintenance personnel to access data related to a failure event.

19. What type of instrument maintenance can be performed by certificated A & P mechanics?

20. Name at three systems or components that provide input to the flight management computer (FMC)?

Multiple Choices Questions

1. Aircraft instrument panels are generally shock mounted to absorb:
a. all vibration
b. low frequency, high amplitude shocks
c. high frequency, high amplitude shocks

2. Aircraft instruments should be marked and graduated in accordance with:
a. the instrument manufacturer's specifications
b. both the aircraft and engine manufacturers' specifications
c. the specific aircraft maintenance or flight manual

3. What marking color is used to indicate if a cover glass has slipped?
a. red
b. white
c. yellow

4. The green arc on an aircraft temperature gauge indicates:
a. the instrument is not calibrated
b. the desirable temperature range
c. a low, unsafe temperature range

5. Which instruments are connected to an aircraft's pitot static system?
    1. Vertical speed indicator.     2. Cabin altimeter.     3. Altimeter.
    4. Cabin rate‐of‐change indicator.     5. Airspeed indicator.
a. 1, 2, 3, 4, and 5
b. 1, 2, and 4
c. 1, 3, and 5

6. An aircraft instrument panel is electrically bonded to the aircraft structure to:
a. act as a restraint strap
b. provide current return paths
c. aid in the panel installation

7 A radar altimeter indicates
a. flight level (pressure) altitude
b. altitude above sea level
c. altitude above ground level

8 When installing an instrument in an aircraft, who is responsible for making sure it is properly marked?
a. The aircraft owner
b. The instrument installer
c. The instrument manufacturer

9. Where may a person look for the information necessary to determine the required markings on an engine instrument?
    1. Engine manufacturer's specifications.          2. Aircraft flight manual.
    3. Instrument manufacturer's specifications.    4. Aircraft maintenance manual.
a. 2 or 4
b. 1 or 4
c. 2 or 3

10. A certificated mechanic with airframe and powerplant ratings may:
a. perform minor repairs to aircraft instruments
b. perform minor repairs and minor alterations to aircraft instruments
c. not perform repairs to aircraft instruments

11. Which instruments are connected to an aircraft's static pressure system only?
     1. Vertical speed indicator      2. Cabin altimeter        3. Altimeter
     4. Cabin rate‐of‐change indicator       5. Airspeed indicator
a. 1 and 3
b. 2, 4, and 5
c. 2 and 4

12. If a static pressure system check reveals excessive leakage, the leak(s) may be located by
a. pressurizing the system and adding leak detection dye
b. isolating portions of the line and testing each portion systematically, starting at the instrument connections
c. removing and visually inspecting the line segments

13. Which of the following instrument discrepancies would require replacement of the instrument?
         1. Red line missing                2. Case leaking                3. Glass cracked
         4. Mounting screws loose      5. Case paint chipped      6. Leaking at line B nut
         7. Will not zero out                 8. Fogged
a. 2, 3, 7, 8
b. 1, 4, 6, 7
c. 1, 3, 5, 8

14. The red radial lines on the face of an engine oil pressure gauge indicates:
a. minimum engine safe RPM operating range
b. minimum precautionary safe operating range
c. minimum and/ or maximum safe operating limits

15. A Bourdon tube instrument may be used to indicate
        1. pressure     2. temperature     3. position
a. 1 and 2
b. 1
c. 2 and 3

16. An aircraft magnetic compass is swung to up‐date the compass correction card when :
a. an annual inspection is accomplished on the aircraft
b. the compass is serviced
c. equipment is added that could effect compass deviation

17. When swinging a magnetic compass, the compensators are adjusted to correct for:
a. magnetic influence deviation
b. compass card oscillations
c. magnetic variations

18. The maximum altitude loss permitted during an unpressurized aircraft instrument static pressure system integrity check is:
a. 50 feet in 1 minute
b. 200 feet in 1 minute
c. 100 feet in 1 minute

19. A barometric altimeter indicates pressure altitude when the barometric scale is set at:
a. 29.92 inches Hg
b. 14.7 inches Hg
c. field elevation

20. The function of a CRT in an EFIS is to:
a. allow the pilot to select the appropriate system configuration for the current flight situation
b. display alphanumeric data and representations of aircraft instruments
c. receive and process input signals from aircraft and engine sensors and send the data to the appropriate display

21. Who is authorized to repair an aircraft instrument?
      1. A certified mechanic with an airframe rating.
      2. A certificated repairman with an airframe rating.
      3. A certificated repair station approved for that class instrument.
      4. A certificated airframe repair station.
a. 1, 2, 3, and 4
b. 3 and 4
c. 3

22. A synchro transmitter is connected to a synchro receiver:
a. mechanically through linkage
b. electromagnetically without wires
c. electrically with wires

23. A turn coordinator instrument indicates:
a. the longitudinal attitude of the aircraft during climb and descent
b. both roll and yaw
c. the need for corrections in pitch and bank

24. What does a reciprocating engine manifold pressure gauge indicate when the engine is not operating?
a. Zero pressure
b. The differential between the manifold pressure and the atmospheric pressure
c. The existing atmospheric pressure

25. The Flight Management System coordinates the adjustment of?
a. Flight parameters only
b. Engine parameters only
c. Engine parameters, flight parameters, airframe parameters

26. The system that automatically monitors the airframe and engine systems and alerts the flight crew in case of a system failure is called?

27. An accelerometer is used to monitor acting upon an airframe.
a. Pressures
b. Forces
c. Airflow

28. The engine pressure indicator (EPR) compares
a. The total exhaust pressure to the pressure of the ram air at the inlet of the engine
b. The total manifold pressure to the pressure at the inlet of the engine
c. The total turbine pressure to the pressure of the ram air at the inlet of the engine

29. Thermocouples are used to monitor?
a. Cylinder head temperature
b. Exhaust gas temperature in turbine engines
c. Both A and B

30. What system can be accessed by maintenance personnel to access data related to a failure event
a. ADC

Introduction and Classifying Instruments
Pressure Measuring Instruments
Remote Sensing and Indication
Mechanical Movement Indicators
Temperature Measuring Instruments
Direction Indicating Instruments
Sources of Power for Gyroscopic Instruments
Principles of Gyroscopic Instruments
Common Gyroscopic Instruments
Auto Pilot System
Autopilot Components
Automatic Flight Control System (AFCS)
Flight Director Systems
Electronic Instruments
Electronic Flight Information Systems
Flight Management System (FMS)
Warnings and Cautions
Instrument Installations and Markings